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Geometry Difficulty 2.1 Junior Find the answer

The minute hand on a clock points at the 12. After rotating 120∘120^{\circ} clockwise, which number will it point at?

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Since there are 12 equally spaced numbers and the total angle in a complete circle is 360∘360^{\circ}, then the angle between two consecutive numbers is 360∘÷12=30∘360^{\circ} \div 12=30^{\circ}. To rotate 120∘120^{\circ}, the minute hand must move by 120∘÷30∘=4120^{\circ} \div 30^{\circ}=4 numbers clockwise from the 12. Therefore, the hand will be pointing at the 4.

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